I'm having issues with it as well. During the day sometimes ABSL goes crazy on my LG C8 and the brightness is all over the place. I also get some artifacting (white flickering spots at the top of the screen) during darker scenes or in the menu. When I launch the game and the GeForce Experience pop-up shows up it looks really weird and if I try to press Alt+Z to open the overlay the screen simply goes dark. If I go borderless the screen goes dark again.
I've tried with about 5 different HDMI cables and nothing changed. I wiped my drivers with DDU and installed the latest ones released today by Nvidia, no luck. I've even installed ME: Andromeda to check if maybe it's my TV that's acting up but no, Dolby Vision works just fine on that one (bear in mind it's the same engine), so I don't really know what's up with the implementation in Heat, but it really makes me not want to play it as much as I would otherwise.